Lealone

Overview#

Lealone is a SQL-centric full-stack runtime environment and AI agent. Originating from H2 Database, it has evolved through 3,469+ commits from a database fork into a highly integrated full-stack platform. The core maintainer is codefollower (zhh). The latest development version is 8.0.0-SNAPSHOT, the latest stable release is 6.0.1, and it requires JDK 21.

Database Engine#

• Dual-mode deployment: Supports both embedded and distributed modes
• Complete SQL support: H2 SQL-compatible, with full SELECT/INSERT/UPDATE/DELETE/MERGE/CREATE/ALTER/DROP syntax
• Concurrency & transactions: ACID transactions and MVCC
• Distributed features: Built-in data sharding
• Network layer: Native asynchronous networking

AI Agent Capabilities (v8.0)#

• Interactive agent: Launch dedicated Agent window via -agent flag
• Vibes coding: Natural language input to auto-generate and launch accessible web apps (e.g., Todo apps)
• Self-evolution: Agent can automatically create and execute services for progressive development (internal details TBD)
• LLM integration: Currently configured via SQL-like syntax for Doubao LLM

Microservices & Workflows#

• SQL-driven services: Declarative microservice creation via CREATE SERVICE, auto-registered HTTP routes
• In-SQL invocation: Direct RPC calls via EXECUTE SERVICE
• Workflow orchestration: CREATE WORKFLOW with natural language comments for complex business logic
• Document-as-application: Run a .sql file to launch a complete app with DB, services, and APIs

Architecture Modules#

The project comprises 15 core sub-modules:

• Foundation & communication: lealone-common, lealone-net (async networking), lealone-client, lealone-sci
• Core storage & compute: lealone-sql (SQL engine, inherited from H2), lealone-db (storage engine), lealone-server
• AI extensions: lealone-aote (AI Optimized Transaction Engine), lealone-aose (AI Object Storage Engine), lealone-agent
• Application framework: lealone-orm, lealone-service, lealone-http
• Engineering: lealone-main, lealone-test

Quick Start#

Build:

mvn package -Dmaven.test.skip=true -P ai

Or download pre-built JAR: lealone-8.0.0-SNAPSHOT.jar

Database mode:

java -jar target/lealone-8.0.0-SNAPSHOT.jar

AI Agent mode:

java -jar target/lealone-8.0.0-SNAPSHOT.jar -agent

Document-driven run:

java -jar target/lealone-8.0.0-SNAPSHOT.jar services.sql

Configuration Examples#

LLM config (execute in Agent window):

set llm (
    provider: 'doubao',
    model: 'doubao-seed-2-0-pro-260215',
    api_key: 'your-api-key'
);

Declarative microservice:

create service if not exists my_service (
    hello(name varchar) varchar,
    get_current_time() varchar
);
execute service my_service hello('zhh');

Auto-exposed HTTP endpoint: http://localhost:8080/service/my_service/hello?name=zhh

Caveats#

• AI capabilities currently only support Doubao LLM; other provider support is TBD
• Details of the "self-evolution" mechanism are not documented
• SQL engine partially retains H2 Database copyright (MPL 2.0 / EPL 1.0); Lealone-original code uses SSPL 1.0
• No publicly known production deployment cases or performance benchmarks